1. Field of the Invention
The present invention relates to biological assay systems generally and, more particularly, but not by way of limitation, to a novel biological assay incubator for access by robotic arms, with minimum interruption of the internal environment of the incubator.
2. Background Art
In the field of biological assays, there is a need to hold the test reagents at various temperatures for various lengths of time. This is commonly done in an incubator. The incubator may be hot or cold, depending on the requirements of the assay. In addition to temperature, other environmental conditions may also require control. For example, cell cultures may need a carbon dioxide rich environment. Fermentations may require an excess of oxygen. Many tests are processed in microplates at small working volumes which may be 50 microliters to 200 microliters per well, for example. At these small volumes, evaporation is a concern. Thus, humidity control is often required. Control of any or all of these elements may be incorporated into, and is available in, the incubators on the market at the present time.
As the field of biotechnology research advances, there is an increasing need to run higher numbers of tests. This need is being met with fully automated systems, utilizing robotic arms to transfer test plates from one device to another. The use of robotic arms places additional requirements on the design of the incubators, since a robotic arm must access predefined positions. These positions must be within the reach of the arm, which is often limited by economics, since the size required for the accessible space determines the system cost. Robotic arm systems are commonly used in one of two formats: they are either mounted on a pivot or on a linear track. A pivot mounted arm can access anything within the cylindrical area described by the arm's radius and its vertical reach. A track mounted arm can serve the aisle on both sides of the track. The length of the aisle, of course, is determined by track length, which, again, is a function of economics and available space. In either case, it is desirable to conserve the arm's accessible real estate.
In addition to considerations of economics, a particular problem with conventional robotic arm systems for use with bioassay incubators is that, when the robotic arms access the interiors of the incubators, which occurs periodically and frequently, there is considerable disturbance of the interior environments of the incubators, often through the opening of large areas of the sides of the incubators. This disturbance interferes with temperature, humidity, and/or gas composition control.
Accordingly, it is a principal object of the present invention to provide a bioassay incubator for use with a robotic arm, which incubator provides for a relatively large, yet compact, accessible space for the robotic arm.
It is a further object of the invention to provide such an incubator which permits control of the interior environment of the incubator without significant interference with that environment when the interior of the incubator is accessed by the robotic arm.
It is an additional object of the invention to provide such an incubator which can be simply and economically constructed.
Other objects of the present invention, as well as particular features, elements, and advantages thereof, will be elucidated in, or be apparent from, the following description and the accompanying drawing figures.